Large blades used in mobile ice surfacing machines and those used on paper cutting machines get worn out and dull from their constant extended use over time. These large, expensive, heavy blades which can be up to several feet or more in length often require constant sharpening maintenance to be useful.
Mobile ice surfacing machines, such as Zamboni® are well known for resurfacing ice rink surfaces. Due to the continuous use by ice skaters and the like, indoor and outdoor ice rinks typically require refurbishing their ice surfaces on a regular basis. Over time the sharp edges on ice skates tend to cut into and can gouge the ice surfaces causing uneven surfaces that can be both undesirable and dangerous to the skaters. Also controlling the energy costs in the rinks requires the ice surfaces be maintained at proper thicknesses. Because of their large surface areas mobile ice resurfacing machines have been developed that can traverse and constantly resurface the large ice rink surfaces. These ice resurfacing machines use large longitudinal blades of approximately five to seven feet in length that can weigh up to fifty pounds to eighty pounds or more. The ice resurfacing machines use these large blades to shave and plane the ice surfaces, and also pickup residual snow caused from the shaving. See for example, U.S. Pat. No. 3,917,350 to Bricher. Since the ice surfaces being resurfaced are hard and can include uneven surfaces, the blades on the ice resurfacing machines tend to become worn down and become dull very quickly usually after only five to seven days of use. Using these dull blades is unacceptable since the dull blades can result in rough and wavy surfaces which can be dangerous to skaters and also result in improper pickup of snow off the ice surfaces. The problem arises as to how to sharpen these large longitudinal blades on the ice resurfacing machines. In the United States alone there are an estimated 2,800 ice rinks and in Canada alone there are an estimated 5,000 to 6,000 ice rinks that each have their own ice resurfacing machines that need to have their blades resharpened over time.
The general technique to fix the dull blades is to physically remove the blades from the resurfacing machines and transport them to machine shops that have massive edge sharpening machines. Typically these machine shops will use a large hydraulic type sharpening machine that can weigh upwards of 10,000 pounds or more, can cost up to $100,000 or more, and require space of at least 168 inches in length or more to be used. Further, these heavy industrial machines require substantial training time and expense they can be dangerous to operate, and need expensive maintenance plans to be useful for the ice rinks. Thus, these large hydraulic machines would not be a practical investment for the typical ice rink that needs to have their ice resurfacing machine blades regularly resharpened.
Generally, ice rinks tend to ship out their blades to the machine shops to be resurfaced. However, the act of shipping the blades results in the blades being days and weeks out of commission. In order to send out blades to the machine shops, the ice rinks generally need to keep several blades on hand while the dull blades are being sent out for resharpening services so that their ice resurfacing machines can stay in constant operation. Thus, the headache exists in time, manpower, and shipping costs for having to physically transport dull blades out to remotely located machine shops. Furthermore, the remotely located machine shops do not effectively return sharpened blades having a uniform sharpness. Thus, many resharpened blades must be resent out again. Still furthermore, the machine shops tend to take off in excess of approximately {fraction (1/32)} to approximately {fraction (1/16)} of an inch of the surface of the blades during the resharpening operation, thus, taking off more metal than is generally needed usually after having to do several passes or more during the resharpening operation. The excessive amounts of blade material being removed further results in a shorter lifespan of the blades.
Also by sending out the blades for resharpening, the ice rink operators and their employees do not directly see the results of when their actions cause unnecessary nicks to the blade that requires additional costs and expenses of how much more work needs to done to remove nicks that have been caused by driving the mobile ice resurfacing machine onto the threshold when coming off the rink. The mobile machine operator does not usually realize that when the blades hit this threshold extra nicks are made onto the blade that also must be fixed by additional grinding which also causes further expense and delay in getting the blade back onto the machines.
Thus, the ice rinks can typically spend hundreds of dollars per month with the machine shops to resharpen their blades, and also fix unnecessary problems that they do not directly see the problems they cause, such as nicks from poor driving on the ice.
Some alternative solutions to resharpening blades have centered on using a disposable ice resurfacing blades. See for example, U.S. Pat. No. 4,705,320 to Zamboni. However, these blades are not reusable and still would require the user have several blades in stock. While eliminating the shipping to machine shops function, disposable blades could end up costing as much if not more than traditional machine shop sharpening operations since the cost for having to constantly repurchase new disposable blades on a regular basis must be factored in.
The inventors are aware of other types of various blade sharpening machines. See for example, U.S. Pat. No. 3,834,319 to Kastenbein; U.S. Pat. No. 4,069,620 to Sakcriska; U.S. Pat. No. 4,235,050 to Hannaford et al.; U.S. Pat. No. 4,241,544 to Hampton; U.S. Pat. No. 4,294,043 to Sakcriska; U.S. Pat. No. 4,392,332 to Sakdcriska; U.S. Pat. No. 5,127,194 to Jobin; U.S. Pat. No. 5,480,345 to Bethea and U.S. Pat. No. 5,897,428 to Sakcriska. However, these devices are generally used to sharpen small items such as ice skates, and cannot overcome all the problems with the prior art techniques of sharpening blades on ice resurfacing machines described above.
Similarly, large blades are used in paper cutting machines, which also become dull and unusable after their constant use. The blades used in the paper cutting machines have similar problems to those described above in relation to ice resurfacing blades.
Thus, the need exists for solutions to the above problems with the prior art.